DISTAL BILIARY STENT MIGRATION IN PATIENTS WITH IRRETRIEVABLE COMMON BILE DUCT STONES: A RETROSPECTIVE COMPARISON BETWEEN STRAIGHT AND DOUBLE-PIGTAIL STENTS

Aims Migration of biliary stents is a well-documented problem. Different types of plastic stents (straight or double-pigtail) are used for biliary drainage in patients with irretrievable common bile duct stones (ICBDS). Due to their physical characteristics, double-pigtail stents are expected to migrate less frequently; however, comparisons remain scarce. We aimed to compare the distal migration rate between patients who received either straight or double-pigtail stents in the biliary drainage of ICBDS.

Methods Consecutive patients with ICBDS who received plastic biliary stents at the Venizeleio General Hospital between 2009 and 2019 were retrospectively reviewed. Distal migration was confirmed on follow-up endoscopy when the stent was no longer present at the papillary orifice nor fluoroscopically visible in the bile duct.

Results Among 4524 ERCPs, a total of 618 biliary plastic stent placement procedures (410 patients) were performed for ICBDS: 289 (46.8%) with a straight stent (Group A) and 329 (53.2%) with a double-pigtail stent (Group B). No significant differences were observed between the two groups concerning age, gender, bile duct diameter, placement of single vs multiple biliary stents, as well as use of endoscopic sphincterotomy and balloon sphincteroplasty. The median time period of repeated endoscopy was 7 months (IQR 4-12 months). The rate of distal stent migration was 17.3% (50/289) in group A and 27.4% (90/329) in group B (p=0.003). By Kaplan-Meier analysis, freedom from distal stent migration was 91.6% and 82.7% at 6 months, 78.6% and 72.3% at 12 months, and 73% and 55% at 18 months, for groups A and B respectively (P=0.004, log-rank).

Conclusions Contrary to common perception, pigtail stents are more likely to migrate distally compared with straight stents in patients with ICBDS.